// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Hardware monitoring driver for PMBus devices
 *
 * Copyright (c) 2010, 2011 Ericsson AB.
 * Copyright (c) 2012 Guenter Roeck
 */

#include <linux/debugfs.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/pmbus.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/delay.h>
#include "wb_pmbus.h"

/*
 * Number of additional attribute pointers to allocate
 * with each call to krealloc
 */
#define PMBUS_ATTR_ALLOC_SIZE    (32)
#define PMBUS_NAME_SIZE          (24)
#define PMBUS_RETRY_SLEEP_TIME   (10000)   /* 10ms */
#define PMBUS_RETRY_TIME         (3)

struct pmbus_sensor {
    struct pmbus_sensor *next;
    char name[PMBUS_NAME_SIZE];    /* sysfs sensor name */
    struct device_attribute attribute;
    u8 page;        /* page number */
    u8 phase;        /* phase number, 0xff for all phases */
    u16 reg;        /* register */
    enum pmbus_sensor_classes class;    /* sensor class */
    bool update;        /* runtime sensor update needed */
    bool convert;        /* Whether or not to apply linear/vid/direct */
    int data;        /* Sensor data.
                   Negative if there was a read error */
};
#define to_pmbus_sensor(_attr) \
    container_of(_attr, struct pmbus_sensor, attribute)

struct pmbus_boolean {
    char name[PMBUS_NAME_SIZE];    /* sysfs boolean name */
    struct sensor_device_attribute attribute;
    struct pmbus_sensor *s1;
    struct pmbus_sensor *s2;
};
#define to_pmbus_boolean(_attr) \
    container_of(_attr, struct pmbus_boolean, attribute)

struct pmbus_label {
    char name[PMBUS_NAME_SIZE];    /* sysfs label name */
    struct device_attribute attribute;
    char label[PMBUS_NAME_SIZE];    /* label */
};
#define to_pmbus_label(_attr) \
    container_of(_attr, struct pmbus_label, attribute)

/* Macros for converting between sensor index and register/page/status mask */

#define PB_STATUS_MASK    0xffff
#define PB_REG_SHIFT    16
#define PB_REG_MASK    0x3ff
#define PB_PAGE_SHIFT    26
#define PB_PAGE_MASK    0x3f

#define pb_reg_to_index(page, reg, mask)    (((page) << PB_PAGE_SHIFT) | \
                         ((reg) << PB_REG_SHIFT) | (mask))

#define pb_index_to_page(index)            (((index) >> PB_PAGE_SHIFT) & PB_PAGE_MASK)
#define pb_index_to_reg(index)            (((index) >> PB_REG_SHIFT) & PB_REG_MASK)
#define pb_index_to_mask(index)            ((index) & PB_STATUS_MASK)

struct pmbus_debugfs_entry {
    struct i2c_client *client;
    u8 page;
    u8 reg;
};

static const int pmbus_fan_rpm_mask[] = {
    PB_FAN_1_RPM,
    PB_FAN_2_RPM,
    PB_FAN_1_RPM,
    PB_FAN_2_RPM,
};

static const int pmbus_fan_config_registers[] = {
    PMBUS_FAN_CONFIG_12,
    PMBUS_FAN_CONFIG_12,
    PMBUS_FAN_CONFIG_34,
    PMBUS_FAN_CONFIG_34
};

static const int pmbus_fan_command_registers[] = {
    PMBUS_FAN_COMMAND_1,
    PMBUS_FAN_COMMAND_2,
    PMBUS_FAN_COMMAND_3,
    PMBUS_FAN_COMMAND_4,
};

void wb_pmbus_clear_cache(struct i2c_client *client)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    struct pmbus_sensor *sensor;

    for (sensor = data->sensors; sensor; sensor = sensor->next)
        sensor->data = -ENODATA;
}
EXPORT_SYMBOL_GPL(wb_pmbus_clear_cache);

static int wb_pmbus_set_page_tmp(struct i2c_client *client, int page, int phase)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    int rv;

    if (page < 0)
        return 0;

    if (!(data->info->func[page] & PMBUS_PAGE_VIRTUAL) &&
        data->info->pages > 1 && page != data->currpage) {
        rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
        if (rv < 0)
            return rv;

        rv = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
        if (rv < 0)
            return rv;

        if (rv != page)
            return -EIO;
    }
    data->currpage = page;

    if (data->info->phases[page] && data->currphase != phase &&
        !(data->info->func[page] & PMBUS_PHASE_VIRTUAL)) {
        rv = i2c_smbus_write_byte_data(client, PMBUS_PHASE,
                           phase);
        if (rv)
            return rv;
    }
    data->currphase = phase;

    return 0;
}

int wb_pmbus_set_page(struct i2c_client *client, int page, int phase)
{
    int rv, i;
    struct device *dev = &client->dev;

    for (i = 0; i < PMBUS_RETRY_TIME; i++) {
        rv = wb_pmbus_set_page_tmp(client, page, phase);
        if(rv >= 0){
            return rv;
        }
        if ((i + 1) < PMBUS_RETRY_TIME) {
            usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
        }
    }
    dev_dbg(dev, "wb_pmbus_set_page failed, page=%d, phase=%d, rv=%d\n",
        page, phase, rv);
    return rv;
}
EXPORT_SYMBOL_GPL(wb_pmbus_set_page);

static int wb_pmbus_write_byte_tmp(struct i2c_client *client, int page, u8 value)
{
    int rv;

    rv = wb_pmbus_set_page(client, page, 0xff);
    if (rv < 0)
        return rv;

    return i2c_smbus_write_byte(client, value);
}

int wb_pmbus_write_byte(struct i2c_client *client, int page, u8 value)
{
    int rv, i;
    struct device *dev = &client->dev;

    for (i = 0; i < PMBUS_RETRY_TIME; i++) {
        rv = wb_pmbus_write_byte_tmp(client, page, value);
        if(rv >= 0){
            return rv;
        }
        if ((i + 1) < PMBUS_RETRY_TIME) {
            usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
        }
    }
    dev_dbg(dev, "wb_pmbus_write_byte failed, page=%d, value=0x%x, rv: %d\n",
        page, value, rv);
    return rv;
}

EXPORT_SYMBOL_GPL(wb_pmbus_write_byte);

/*
 * _pmbus_write_byte() is similar to pmbus_write_byte(), but checks if
 * a device specific mapping function exists and calls it if necessary.
 */
static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    const struct pmbus_driver_info *info = data->info;
    int status;

    if (info->write_byte) {
        status = info->write_byte(client, page, value);
        if (status != -ENODATA)
            return status;
    }
    return wb_pmbus_write_byte(client, page, value);
}

static int wb_pmbus_write_word_data_tmp(struct i2c_client *client, int page, u8 reg,
              u16 word)
{
    int rv;

    rv = wb_pmbus_set_page(client, page, 0xff);
    if (rv < 0)
        return rv;

    return i2c_smbus_write_word_data(client, reg, word);
}

int wb_pmbus_write_word_data(struct i2c_client *client, int page, u8 reg,
              u16 word)
{
    int rv, i;
    struct device *dev = &client->dev;

    for (i = 0; i < PMBUS_RETRY_TIME; i++) {
        rv = wb_pmbus_write_word_data_tmp(client, page, reg, word);
        if(rv >= 0){
            return rv;
        }
        if ((i + 1) < PMBUS_RETRY_TIME) {
            usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
        }
    }
    dev_dbg(dev, "wb_pmbus_write_word_data failed, page: %d, reg: 0x%x, value: 0x%x, rv: %d\n",
        page, reg, word, rv);
    return rv;

}
EXPORT_SYMBOL_GPL(wb_pmbus_write_word_data);

static int pmbus_write_virt_reg(struct i2c_client *client, int page, int reg,
                u16 word)
{
    int bit;
    int id;
    int rv;

    switch (reg) {
    case PMBUS_VIRT_FAN_TARGET_1 ... PMBUS_VIRT_FAN_TARGET_4:
        id = reg - PMBUS_VIRT_FAN_TARGET_1;
        bit = pmbus_fan_rpm_mask[id];
        rv = wb_pmbus_update_fan(client, page, id, bit, bit, word);
        break;
    default:
        rv = -ENXIO;
        break;
    }

    return rv;
}

/*
 * _pmbus_write_word_data() is similar to pmbus_write_word_data(), but checks if
 * a device specific mapping function exists and calls it if necessary.
 */
static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg,
                  u16 word)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    const struct pmbus_driver_info *info = data->info;
    int status;

    if (info->write_word_data) {
        status = info->write_word_data(client, page, reg, word);
        if (status != -ENODATA)
            return status;
    }

    if (reg >= PMBUS_VIRT_BASE)
        return pmbus_write_virt_reg(client, page, reg, word);

    return wb_pmbus_write_word_data(client, page, reg, word);
}

int wb_pmbus_update_fan(struct i2c_client *client, int page, int id,
             u8 config, u8 mask, u16 command)
{
    int from;
    int rv;
    u8 to;

    from = wb_pmbus_read_byte_data(client, page,
                    pmbus_fan_config_registers[id]);
    if (from < 0)
        return from;

    to = (from & ~mask) | (config & mask);
    if (to != from) {
        rv = wb_pmbus_write_byte_data(client, page,
                       pmbus_fan_config_registers[id], to);
        if (rv < 0)
            return rv;
    }

    return _pmbus_write_word_data(client, page,
                      pmbus_fan_command_registers[id], command);
}
EXPORT_SYMBOL_GPL(wb_pmbus_update_fan);

static int wb_pmbus_read_word_data_tmp(struct i2c_client *client, int page, int phase, u8 reg)
{
    int rv;

    rv = wb_pmbus_set_page(client, page, phase);
    if (rv < 0)
        return rv;

    return i2c_smbus_read_word_data(client, reg);
}

int wb_pmbus_read_word_data(struct i2c_client *client, int page, int phase, u8 reg)
{
    int rv, i;
    struct device *dev = &client->dev;

    for (i = 0; i < PMBUS_RETRY_TIME; i++) {
        rv = wb_pmbus_read_word_data_tmp(client, page, phase, reg);
        if(rv >= 0){
            return rv;
        }
        if ((i + 1) < PMBUS_RETRY_TIME) {
            usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
        }
    }
    dev_dbg(dev, "wb_pmbus_read_word_data failed, page: %d, phase: %d, reg: 0x%x, rv: %d\n",
        page, phase, reg, rv);
    return rv;
}
EXPORT_SYMBOL_GPL(wb_pmbus_read_word_data);

static int pmbus_read_virt_reg(struct i2c_client *client, int page, int reg)
{
    int rv;
    int id;

    switch (reg) {
    case PMBUS_VIRT_FAN_TARGET_1 ... PMBUS_VIRT_FAN_TARGET_4:
        id = reg - PMBUS_VIRT_FAN_TARGET_1;
        rv = wb_pmbus_get_fan_rate_device(client, page, id, rpm);
        break;
    default:
        rv = -ENXIO;
        break;
    }

    return rv;
}

/*
 * _pmbus_read_word_data() is similar to wb_pmbus_read_word_data(), but checks if
 * a device specific mapping function exists and calls it if necessary.
 */
static int _pmbus_read_word_data(struct i2c_client *client, int page,
                 int phase, int reg)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    const struct pmbus_driver_info *info = data->info;
    int status;

    if (info->read_word_data) {
        status = info->read_word_data(client, page, phase, reg);
        if (status != -ENODATA)
            return status;
    }

    if (reg >= PMBUS_VIRT_BASE)
        return pmbus_read_virt_reg(client, page, reg);

    return wb_pmbus_read_word_data(client, page, phase, reg);
}

/* Same as above, but without phase parameter, for use in check functions */
static int __pmbus_read_word_data(struct i2c_client *client, int page, int reg)
{
    return _pmbus_read_word_data(client, page, 0xff, reg);
}

static int wb_pmbus_read_byte_data_tmp(struct i2c_client *client, int page, u8 reg)
{
    int rv;

    rv = wb_pmbus_set_page(client, page, 0xff);
    if (rv < 0)
        return rv;

    return i2c_smbus_read_byte_data(client, reg);
}

int wb_pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg)
{
    int rv, i;
    struct device *dev = &client->dev;

    for (i = 0; i < PMBUS_RETRY_TIME; i++) {
        rv = wb_pmbus_read_byte_data_tmp(client, page, reg);
        if(rv >= 0){
            return rv;
        }
        if ((i + 1) < PMBUS_RETRY_TIME) {
            usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
        }
    }
    dev_dbg(dev, "wb_pmbus_read_byte_data failed, page: %d, reg: 0x%x, rv: %d\n",
        page, reg, rv);
    return rv;
}
EXPORT_SYMBOL_GPL(wb_pmbus_read_byte_data);

static int wb_pmbus_write_byte_data_tmp(struct i2c_client *client, int page, u8 reg, u8 value)
{
    int rv;

    rv = wb_pmbus_set_page(client, page, 0xff);
    if (rv < 0)
        return rv;

    return i2c_smbus_write_byte_data(client, reg, value);
}

int wb_pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value)
{
    int rv, i;
    struct device *dev = &client->dev;

    for (i = 0; i < PMBUS_RETRY_TIME; i++) {
        rv = wb_pmbus_write_byte_data_tmp(client, page, reg, value);
        if(rv >= 0){
            return rv;
        }
        if ((i + 1) < PMBUS_RETRY_TIME) {
            usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
        }
    }
    dev_dbg(dev, "wb_pmbus_write_byte_data failed, page: %d, reg: 0x%x, value: 0x%x, rv: %d\n",
        page, reg, value, rv);
    return rv;
}
EXPORT_SYMBOL_GPL(wb_pmbus_write_byte_data);

int wb_pmbus_update_byte_data(struct i2c_client *client, int page, u8 reg,
               u8 mask, u8 value)
{
    unsigned int tmp;
    int rv;

    rv = wb_pmbus_read_byte_data(client, page, reg);
    if (rv < 0)
        return rv;

    tmp = (rv & ~mask) | (value & mask);

    if (tmp != rv)
        rv = wb_pmbus_write_byte_data(client, page, reg, tmp);

    return rv;
}
EXPORT_SYMBOL_GPL(wb_pmbus_update_byte_data);

/*
 * _pmbus_read_byte_data() is similar to wb_pmbus_read_byte_data(), but checks if
 * a device specific mapping function exists and calls it if necessary.
 */
static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    const struct pmbus_driver_info *info = data->info;
    int status;

    if (info->read_byte_data) {
        status = info->read_byte_data(client, page, reg);
        if (status != -ENODATA)
            return status;
    }
    return wb_pmbus_read_byte_data(client, page, reg);
}

static struct pmbus_sensor *pmbus_find_sensor(struct pmbus_data *data, int page,
                          int reg)
{
    struct pmbus_sensor *sensor;

    for (sensor = data->sensors; sensor; sensor = sensor->next) {
        if (sensor->page == page && sensor->reg == reg)
            return sensor;
    }

    return ERR_PTR(-EINVAL);
}

static int pmbus_get_fan_rate(struct i2c_client *client, int page, int id,
                  enum pmbus_fan_mode mode,
                  bool from_cache)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    bool want_rpm, have_rpm;
    struct pmbus_sensor *s;
    int config;
    int reg;

    want_rpm = (mode == rpm);

    if (from_cache) {
        reg = want_rpm ? PMBUS_VIRT_FAN_TARGET_1 : PMBUS_VIRT_PWM_1;
        s = pmbus_find_sensor(data, page, reg + id);
        if (IS_ERR(s))
            return PTR_ERR(s);

        return s->data;
    }

    config = wb_pmbus_read_byte_data(client, page,
                      pmbus_fan_config_registers[id]);
    if (config < 0)
        return config;

    have_rpm = !!(config & pmbus_fan_rpm_mask[id]);
    if (want_rpm == have_rpm)
        return wb_pmbus_read_word_data(client, page, 0xff,
                        pmbus_fan_command_registers[id]);

    /* Can't sensibly map between RPM and PWM, just return zero */
    return 0;
}

int wb_pmbus_get_fan_rate_device(struct i2c_client *client, int page, int id,
                  enum pmbus_fan_mode mode)
{
    return pmbus_get_fan_rate(client, page, id, mode, false);
}
EXPORT_SYMBOL_GPL(wb_pmbus_get_fan_rate_device);

int wb_pmbus_get_fan_rate_cached(struct i2c_client *client, int page, int id,
                  enum pmbus_fan_mode mode)
{
    return pmbus_get_fan_rate(client, page, id, mode, true);
}
EXPORT_SYMBOL_GPL(wb_pmbus_get_fan_rate_cached);

static void pmbus_clear_fault_page(struct i2c_client *client, int page)
{
    _pmbus_write_byte(client, page, PMBUS_CLEAR_FAULTS);
}

void wb_pmbus_clear_faults(struct i2c_client *client)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    int i;

    for (i = 0; i < data->info->pages; i++)
        pmbus_clear_fault_page(client, i);
}
EXPORT_SYMBOL_GPL(wb_pmbus_clear_faults);

static int pmbus_check_status_cml(struct i2c_client *client)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    int status, status2;

    status = data->read_status(client, -1);
    if (status < 0 || (status & PB_STATUS_CML)) {
        status2 = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML);
        if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND))
            return -EIO;
    }
    return 0;
}

static bool pmbus_check_register(struct i2c_client *client,
                 int (*func)(struct i2c_client *client,
                         int page, int reg),
                 int page, int reg)
{
    int rv;
    struct pmbus_data *data = i2c_get_clientdata(client);

    rv = func(client, page, reg);
    if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
        rv = pmbus_check_status_cml(client);
    pmbus_clear_fault_page(client, -1);
    return rv >= 0;
}

static bool pmbus_check_status_register(struct i2c_client *client, int page)
{
    int status;
    struct pmbus_data *data = i2c_get_clientdata(client);

    status = data->read_status(client, page);
    if (status >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK) &&
        (status & PB_STATUS_CML)) {
        status = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML);
        if (status < 0 || (status & PB_CML_FAULT_INVALID_COMMAND))
            status = -EIO;
    }

    pmbus_clear_fault_page(client, -1);
    return status >= 0;
}

bool wb_pmbus_check_byte_register(struct i2c_client *client, int page, int reg)
{
    return pmbus_check_register(client, _pmbus_read_byte_data, page, reg);
}
EXPORT_SYMBOL_GPL(wb_pmbus_check_byte_register);

bool wb_pmbus_check_word_register(struct i2c_client *client, int page, int reg)
{
    return pmbus_check_register(client, __pmbus_read_word_data, page, reg);
}
EXPORT_SYMBOL_GPL(wb_pmbus_check_word_register);

const struct pmbus_driver_info *wb_pmbus_get_driver_info(struct i2c_client *client)
{
    struct pmbus_data *data = i2c_get_clientdata(client);

    return data->info;
}
EXPORT_SYMBOL_GPL(wb_pmbus_get_driver_info);

static int pmbus_read_status_byte(struct i2c_client *client, int page)
{
    return _pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE);
}

static int pmbus_read_status_word(struct i2c_client *client, int page)
{
    return _pmbus_read_word_data(client, page, 0xff, PMBUS_STATUS_WORD);
}

static int pmbus_get_status(struct i2c_client *client, int page, int reg)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    int status;

    switch (reg) {
    case PMBUS_STATUS_WORD:
        status = data->read_status(client, page);
        if ((status < 0) || (data->has_status_word && (status == 0xffff))
            || (!data->has_status_word && (status == 0xff))) {
            if (data->has_status_word) {
                data->read_status = pmbus_read_status_byte;
            } else {
                data->read_status = pmbus_read_status_word;
            }
            data->has_status_word = !data->has_status_word;
            status = data->read_status(client, page);
        }
        break;
    default:
        status = _pmbus_read_byte_data(client, page, reg);
        break;
    }
    if (status < 0)
        wb_pmbus_clear_faults(client);
    return status;
}

static void pmbus_update_sensor_data(struct i2c_client *client, struct pmbus_sensor *sensor)
{
    if (sensor->data < 0 || sensor->update)
        sensor->data = _pmbus_read_word_data(client, sensor->page,
                             sensor->phase, sensor->reg);
}

/*
 * Convert linear sensor values to milli- or micro-units
 * depending on sensor type.
 */
static s64 pmbus_reg2data_linear(struct pmbus_data *data,
                 struct pmbus_sensor *sensor)
{
    s16 exponent;
    s32 mantissa;
    s64 val;

    if (sensor->class == PSC_VOLTAGE_OUT) {    /* LINEAR16 */
        exponent = data->exponent[sensor->page];
        mantissa = (u16) sensor->data;
    } else {                /* LINEAR11 */
        exponent = ((s16)sensor->data) >> 11;
        mantissa = ((s16)((sensor->data & 0x7ff) << 5)) >> 5;
    }

    val = mantissa;

    /* scale result to milli-units for all sensors except fans */
    if (sensor->class != PSC_FAN)
        val = val * 1000LL;

    /* scale result to micro-units for power sensors */
    if (sensor->class == PSC_POWER)
        val = val * 1000LL;

    if (exponent >= 0)
        val <<= exponent;
    else
        val >>= -exponent;

    return val;
}

/*
 * Convert direct sensor values to milli- or micro-units
 * depending on sensor type.
 */
static s64 pmbus_reg2data_direct(struct pmbus_data *data,
                 struct pmbus_sensor *sensor)
{
    s64 b, val = (s16)sensor->data;
    s32 m, R;

    m = data->info->m[sensor->class];
    b = data->info->b[sensor->class];
    R = data->info->R[sensor->class];

    if (m == 0)
        return 0;

    /* X = 1/m * (Y * 10^-R - b) */
    R = -R;
    /* scale result to milli-units for everything but fans */
    if (!(sensor->class == PSC_FAN || sensor->class == PSC_PWM)) {
        R += 3;
        b *= 1000;
    }

    /* scale result to micro-units for power sensors */
    if (sensor->class == PSC_POWER) {
        R += 3;
        b *= 1000;
    }

    while (R > 0) {
        val *= 10;
        R--;
    }
    while (R < 0) {
        val = div_s64(val + 5LL, 10L);  /* round closest */
        R++;
    }

    val = div_s64(val - b, m);
    return val;
}

/*
 * Convert VID sensor values to milli- or micro-units
 * depending on sensor type.
 */
static s64 pmbus_reg2data_vid(struct pmbus_data *data,
                  struct pmbus_sensor *sensor)
{
    long val = sensor->data;
    long rv = 0;

    switch (data->info->vrm_version[sensor->page]) {
    case vr11:
        if (val >= 0x02 && val <= 0xb2)
            rv = DIV_ROUND_CLOSEST(160000 - (val - 2) * 625, 100);
        break;
    case vr12:
        if (val >= 0x01)
            rv = 250 + (val - 1) * 5;
        break;
    case vr13:
        if (val >= 0x01)
            rv = 500 + (val - 1) * 10;
        break;
    case imvp9:
        if (val >= 0x01)
            rv = 200 + (val - 1) * 10;
        break;
    case amd625mv:
        if (val >= 0x0 && val <= 0xd8)
            rv = DIV_ROUND_CLOSEST(155000 - val * 625, 100);
        break;
    }
    return rv;
}

static s64 pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
{
    s64 val;

    if (!sensor->convert)
        return sensor->data;

    switch (data->info->format[sensor->class]) {
    case direct:
        val = pmbus_reg2data_direct(data, sensor);
        break;
    case vid:
        val = pmbus_reg2data_vid(data, sensor);
        break;
    case linear:
    default:
        val = pmbus_reg2data_linear(data, sensor);
        break;
    }
    return val;
}

#define MAX_MANTISSA    (1023 * 1000)
#define MIN_MANTISSA    (511 * 1000)

static u16 pmbus_data2reg_linear(struct pmbus_data *data,
                 struct pmbus_sensor *sensor, s64 val)
{
    s16 exponent = 0, mantissa;
    bool negative = false;

    /* simple case */
    if (val == 0)
        return 0;

    if (sensor->class == PSC_VOLTAGE_OUT) {
        /* LINEAR16 does not support negative voltages */
        if (val < 0)
            return 0;

        /*
         * For a static exponents, we don't have a choice
         * but to adjust the value to it.
         */
        if (data->exponent[sensor->page] < 0)
            val <<= -data->exponent[sensor->page];
        else
            val >>= data->exponent[sensor->page];
        val = DIV_ROUND_CLOSEST_ULL(val, 1000);
        return clamp_val(val, 0, 0xffff);
    }

    if (val < 0) {
        negative = true;
        val = -val;
    }

    /* Power is in uW. Convert to mW before converting. */
    if (sensor->class == PSC_POWER)
        val = DIV_ROUND_CLOSEST_ULL(val, 1000);

    /*
     * For simplicity, convert fan data to milli-units
     * before calculating the exponent.
     */
    if (sensor->class == PSC_FAN)
        val = val * 1000LL;

    /* Reduce large mantissa until it fits into 10 bit */
    while (val >= MAX_MANTISSA && exponent < 15) {
        exponent++;
        val >>= 1;
    }
    /* Increase small mantissa to improve precision */
    while (val < MIN_MANTISSA && exponent > -15) {
        exponent--;
        val <<= 1;
    }

    /* Convert mantissa from milli-units to units */
    mantissa = clamp_val(DIV_ROUND_CLOSEST_ULL(val, 1000), 0, 0x3ff);

    /* restore sign */
    if (negative)
        mantissa = -mantissa;

    /* Convert to 5 bit exponent, 11 bit mantissa */
    return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
}

static u16 pmbus_data2reg_direct(struct pmbus_data *data,
                 struct pmbus_sensor *sensor, s64 val)
{
    s64 b;
    s32 m, R;

    m = data->info->m[sensor->class];
    b = data->info->b[sensor->class];
    R = data->info->R[sensor->class];

    /* Power is in uW. Adjust R and b. */
    if (sensor->class == PSC_POWER) {
        R -= 3;
        b *= 1000;
    }

    /* Calculate Y = (m * X + b) * 10^R */
    if (!(sensor->class == PSC_FAN || sensor->class == PSC_PWM)) {
        R -= 3;        /* Adjust R and b for data in milli-units */
        b *= 1000;
    }
    val = val * m + b;

    while (R > 0) {
        val *= 10;
        R--;
    }
    while (R < 0) {
        val = div_s64(val + 5LL, 10L);  /* round closest */
        R++;
    }

    return (u16)clamp_val(val, S16_MIN, S16_MAX);
}

static u16 pmbus_data2reg_vid(struct pmbus_data *data,
                  struct pmbus_sensor *sensor, s64 val)
{
    val = clamp_val(val, 500, 1600);

    return 2 + DIV_ROUND_CLOSEST_ULL((1600LL - val) * 100LL, 625);
}

static u16 pmbus_data2reg(struct pmbus_data *data,
              struct pmbus_sensor *sensor, s64 val)
{
    u16 regval;

    if (!sensor->convert)
        return val;

    switch (data->info->format[sensor->class]) {
    case direct:
        regval = pmbus_data2reg_direct(data, sensor, val);
        break;
    case vid:
        regval = pmbus_data2reg_vid(data, sensor, val);
        break;
    case linear:
    default:
        regval = pmbus_data2reg_linear(data, sensor, val);
        break;
    }
    return regval;
}

/*
 * Return boolean calculated from converted data.
 * <index> defines a status register index and mask.
 * The mask is in the lower 8 bits, the register index is in bits 8..23.
 *
 * The associated pmbus_boolean structure contains optional pointers to two
 * sensor attributes. If specified, those attributes are compared against each
 * other to determine if a limit has been exceeded.
 *
 * If the sensor attribute pointers are NULL, the function returns true if
 * (status[reg] & mask) is true.
 *
 * If sensor attribute pointers are provided, a comparison against a specified
 * limit has to be performed to determine the boolean result.
 * In this case, the function returns true if v1 >= v2 (where v1 and v2 are
 * sensor values referenced by sensor attribute pointers s1 and s2).
 *
 * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>.
 * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>.
 *
 * If a negative value is stored in any of the referenced registers, this value
 * reflects an error code which will be returned.
 */
static int pmbus_get_boolean(struct i2c_client *client, struct pmbus_boolean *b,
                 int index)
{
    struct pmbus_data *data = i2c_get_clientdata(client);
    struct pmbus_sensor *s1 = b->s1;
    struct pmbus_sensor *s2 = b->s2;
    u16 mask = pb_index_to_mask(index);
    u8 page = pb_index_to_page(index);
    u16 reg = pb_index_to_reg(index);
    int ret, status;
    u16 regval;

    mutex_lock(&data->update_lock);
    status = pmbus_get_status(client, page, reg);
    if (status < 0) {
        ret = status;
        goto unlock;
    }

    if (s1)
        pmbus_update_sensor_data(client, s1);
    if (s2)
        pmbus_update_sensor_data(client, s2);

    regval = status & mask;
    if (s1 && s2) {
        s64 v1, v2;

        if (s1->data < 0) {
            ret = s1->data;
            goto unlock;
        }
        if (s2->data < 0) {
            ret = s2->data;
            goto unlock;
        }

        v1 = pmbus_reg2data(data, s1);
        v2 = pmbus_reg2data(data, s2);
        ret = !!(regval && v1 >= v2);
    } else {
        ret = !!regval;
    }
unlock:
    mutex_unlock(&data->update_lock);
    return ret;
}

static ssize_t pmbus_show_boolean(struct device *dev,
                  struct device_attribute *da, char *buf)
{
    struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    struct pmbus_boolean *boolean = to_pmbus_boolean(attr);
    struct i2c_client *client = to_i2c_client(dev->parent);
    int val;

    val = pmbus_get_boolean(client, boolean, attr->index);
    if (val < 0)
        return val;
    return snprintf(buf, PAGE_SIZE, "%d\n", val);
}

static ssize_t pmbus_show_sensor(struct device *dev,
                 struct device_attribute *devattr, char *buf)
{
    struct i2c_client *client = to_i2c_client(dev->parent);
    struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
    struct pmbus_data *data = i2c_get_clientdata(client);
    ssize_t ret;

    mutex_lock(&data->update_lock);
    pmbus_update_sensor_data(client, sensor);
    if (sensor->data < 0)
        ret = sensor->data;
    else
        ret = snprintf(buf, PAGE_SIZE, "%lld\n", pmbus_reg2data(data, sensor));
    mutex_unlock(&data->update_lock);
    return ret;
}

static ssize_t pmbus_set_sensor(struct device *dev,
                struct device_attribute *devattr,
                const char *buf, size_t count)
{
    struct i2c_client *client = to_i2c_client(dev->parent);
    struct pmbus_data *data = i2c_get_clientdata(client);
    struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
    ssize_t rv = count;
    s64 val;
    int ret;
    u16 regval;

    if (kstrtos64(buf, 10, &val) < 0)
        return -EINVAL;

    mutex_lock(&data->update_lock);
    regval = pmbus_data2reg(data, sensor, val);
    ret = _pmbus_write_word_data(client, sensor->page, sensor->reg, regval);
    if (ret < 0)
        rv = ret;
    else
        sensor->data = regval;
    mutex_unlock(&data->update_lock);
    return rv;
}

static ssize_t pmbus_show_label(struct device *dev,
                struct device_attribute *da, char *buf)
{
    struct pmbus_label *label = to_pmbus_label(da);

    return snprintf(buf, PAGE_SIZE, "%s\n", label->label);
}

static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
{
    if (data->num_attributes >= data->max_attributes - 1) {
        int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE;
        void *new_attrs = devm_krealloc(data->dev, data->group.attrs,
                        new_max_attrs * sizeof(void *),
                        GFP_KERNEL);
        if (!new_attrs)
            return -ENOMEM;
        data->group.attrs = new_attrs;
        data->max_attributes = new_max_attrs;
    }

    data->group.attrs[data->num_attributes++] = attr;
    data->group.attrs[data->num_attributes] = NULL;
    return 0;
}

static void pmbus_dev_attr_init(struct device_attribute *dev_attr,
                const char *name,
                umode_t mode,
                ssize_t (*show)(struct device *dev,
                        struct device_attribute *attr,
                        char *buf),
                ssize_t (*store)(struct device *dev,
                         struct device_attribute *attr,
                         const char *buf, size_t count))
{
    sysfs_attr_init(&dev_attr->attr);
    dev_attr->attr.name = name;
    dev_attr->attr.mode = mode;
    dev_attr->show = show;
    dev_attr->store = store;
}

static void pmbus_attr_init(struct sensor_device_attribute *a,
                const char *name,
                umode_t mode,
                ssize_t (*show)(struct device *dev,
                        struct device_attribute *attr,
                        char *buf),
                ssize_t (*store)(struct device *dev,
                         struct device_attribute *attr,
                         const char *buf, size_t count),
                int idx)
{
    pmbus_dev_attr_init(&a->dev_attr, name, mode, show, store);
    a->index = idx;
}

static int pmbus_add_boolean(struct pmbus_data *data,
                 const char *name, const char *type, int seq,
                 struct pmbus_sensor *s1,
                 struct pmbus_sensor *s2,
                 u8 page, u16 reg, u16 mask)
{
    struct pmbus_boolean *boolean;
    struct sensor_device_attribute *a;

    if (WARN((s1 && !s2) || (!s1 && s2), "Bad s1/s2 parameters\n"))
        return -EINVAL;

    boolean = devm_kzalloc(data->dev, sizeof(*boolean), GFP_KERNEL);
    if (!boolean)
        return -ENOMEM;

    a = &boolean->attribute;

    snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
         name, seq, type);
    boolean->s1 = s1;
    boolean->s2 = s2;
    pmbus_attr_init(a, boolean->name, 0444, pmbus_show_boolean, NULL,
            pb_reg_to_index(page, reg, mask));

    return pmbus_add_attribute(data, &a->dev_attr.attr);
}

static struct pmbus_sensor *pmbus_add_sensor(struct pmbus_data *data,
                         const char *name, const char *type,
                         int seq, int page, int phase,
                         int reg,
                         enum pmbus_sensor_classes class,
                         bool update, bool readonly,
                         bool convert)
{
    struct pmbus_sensor *sensor;
    struct device_attribute *a;

    sensor = devm_kzalloc(data->dev, sizeof(*sensor), GFP_KERNEL);
    if (!sensor)
        return NULL;
    a = &sensor->attribute;

    if (type)
        snprintf(sensor->name, sizeof(sensor->name), "%s%d_%s",
             name, seq, type);
    else
        snprintf(sensor->name, sizeof(sensor->name), "%s%d",
             name, seq);

    if (data->flags & PMBUS_WRITE_PROTECTED)
        readonly = true;

    sensor->page = page;
    sensor->phase = phase;
    sensor->reg = reg;
    sensor->class = class;
    sensor->update = update;
    sensor->convert = convert;
    sensor->data = -ENODATA;
    pmbus_dev_attr_init(a, sensor->name,
                readonly ? 0444 : 0644,
                pmbus_show_sensor, pmbus_set_sensor);

    if (pmbus_add_attribute(data, &a->attr))
        return NULL;

    sensor->next = data->sensors;
    data->sensors = sensor;

    return sensor;
}

static int pmbus_add_label(struct pmbus_data *data,
               const char *name, int seq,
               const char *lstring, int index, int phase)
{
    struct pmbus_label *label;
    struct device_attribute *a;

    label = devm_kzalloc(data->dev, sizeof(*label), GFP_KERNEL);
    if (!label)
        return -ENOMEM;

    a = &label->attribute;

    snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
    if (!index) {
        if (phase == 0xff)
            strncpy(label->label, lstring,
                sizeof(label->label) - 1);
        else
            snprintf(label->label, sizeof(label->label), "%s.%d",
                 lstring, phase);
    } else {
        if (phase == 0xff)
            snprintf(label->label, sizeof(label->label), "%s%d",
                 lstring, index);
        else
            snprintf(label->label, sizeof(label->label), "%s%d.%d",
                 lstring, index, phase);
    }

    pmbus_dev_attr_init(a, label->name, 0444, pmbus_show_label, NULL);
    return pmbus_add_attribute(data, &a->attr);
}

/*
 * Search for attributes. Allocate sensors, booleans, and labels as needed.
 */

/*
 * The pmbus_limit_attr structure describes a single limit attribute
 * and its associated alarm attribute.
 */
struct pmbus_limit_attr {
    u16 reg;        /* Limit register */
    u16 sbit;        /* Alarm attribute status bit */
    bool update;        /* True if register needs updates */
    bool low;        /* True if low limit; for limits with compare
                   functions only */
    const char *attr;    /* Attribute name */
    const char *alarm;    /* Alarm attribute name */
};

/*
 * The pmbus_sensor_attr structure describes one sensor attribute. This
 * description includes a reference to the associated limit attributes.
 */
struct pmbus_sensor_attr {
    u16 reg;            /* sensor register */
    u16 gbit;            /* generic status bit */
    u8 nlimit;            /* # of limit registers */
    enum pmbus_sensor_classes class;/* sensor class */
    const char *label;        /* sensor label */
    bool paged;            /* true if paged sensor */
    bool update;            /* true if update needed */
    bool compare;            /* true if compare function needed */
    u32 func;            /* sensor mask */
    u32 sfunc;            /* sensor status mask */
    int sreg;            /* status register */
    const struct pmbus_limit_attr *limit;/* limit registers */
};

/*
 * Add a set of limit attributes and, if supported, the associated
 * alarm attributes.
 * returns 0 if no alarm register found, 1 if an alarm register was found,
 * < 0 on errors.
 */
static int pmbus_add_limit_attrs(struct i2c_client *client,
                 struct pmbus_data *data,
                 const struct pmbus_driver_info *info,
                 const char *name, int index, int page,
                 struct pmbus_sensor *base,
                 const struct pmbus_sensor_attr *attr)
{
    const struct pmbus_limit_attr *l = attr->limit;
    int nlimit = attr->nlimit;
    int have_alarm = 0;
    int i, ret;
    struct pmbus_sensor *curr;

    for (i = 0; i < nlimit; i++) {
        if (wb_pmbus_check_word_register(client, page, l->reg)) {
            curr = pmbus_add_sensor(data, name, l->attr, index,
                        page, 0xff, l->reg, attr->class,
                        attr->update || l->update,
                        false, true);
            if (!curr)
                return -ENOMEM;
            if (l->sbit && (info->func[page] & attr->sfunc)) {
                ret = pmbus_add_boolean(data, name,
                    l->alarm, index,
                    attr->compare ?  l->low ? curr : base
                              : NULL,
                    attr->compare ? l->low ? base : curr
                              : NULL,
                    page, attr->sreg, l->sbit);
                if (ret)
                    return ret;
                have_alarm = 1;
            }
        }
        l++;
    }
    return have_alarm;
}

static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
                      struct pmbus_data *data,
                      const struct pmbus_driver_info *info,
                      const char *name,
                      int index, int page, int phase,
                      const struct pmbus_sensor_attr *attr,
                      bool paged)
{
    struct pmbus_sensor *base;
    bool upper = !!(attr->gbit & 0xff00);    /* need to check STATUS_WORD */
    int ret;

    if (attr->label) {
        ret = pmbus_add_label(data, name, index, attr->label,
                      paged ? page + 1 : 0, phase);
        if (ret)
            return ret;
    }
    base = pmbus_add_sensor(data, name, "input", index, page, phase,
                attr->reg, attr->class, true, true, true);
    if (!base)
        return -ENOMEM;
    /* No limit and alarm attributes for phase specific sensors */
    if (attr->sfunc && phase == 0xff) {
        ret = pmbus_add_limit_attrs(client, data, info, name,
                        index, page, base, attr);
        if (ret < 0)
            return ret;
        /*
         * Add generic alarm attribute only if there are no individual
         * alarm attributes, if there is a global alarm bit, and if
         * the generic status register (word or byte, depending on
         * which global bit is set) for this page is accessible.
         */
        if (!ret && attr->gbit &&
            (!upper || (upper && data->has_status_word)) &&
            pmbus_check_status_register(client, page)) {
            ret = pmbus_add_boolean(data, name, "alarm", index,
                        NULL, NULL,
                        page, PMBUS_STATUS_WORD,
                        attr->gbit);
            if (ret)
                return ret;
        }
    }
    return 0;
}

static bool pmbus_sensor_is_paged(const struct pmbus_driver_info *info,
                  const struct pmbus_sensor_attr *attr)
{
    int p;

    if (attr->paged)
        return true;

    /*
     * Some attributes may be present on more than one page despite
     * not being marked with the paged attribute. If that is the case,
     * then treat the sensor as being paged and add the page suffix to the
     * attribute name.
     * We don't just add the paged attribute to all such attributes, in
     * order to maintain the un-suffixed labels in the case where the
     * attribute is only on page 0.
     */
    for (p = 1; p < info->pages; p++) {
        if (info->func[p] & attr->func)
            return true;
    }
    return false;
}

static int pmbus_add_sensor_attrs(struct i2c_client *client,
                  struct pmbus_data *data,
                  const char *name,
                  const struct pmbus_sensor_attr *attrs,
                  int nattrs)
{
    const struct pmbus_driver_info *info = data->info;
    int index, i;
    int ret;

    index = 1;
    for (i = 0; i < nattrs; i++) {
        int page, pages;
        bool paged = pmbus_sensor_is_paged(info, attrs);

        pages = paged ? info->pages : 1;
        for (page = 0; page < pages; page++) {
            if (!(info->func[page] & attrs->func))
                continue;
            ret = pmbus_add_sensor_attrs_one(client, data, info,
                             name, index, page,
                             0xff, attrs, paged);
            if (ret)
                return ret;
            index++;
            if (info->phases[page]) {
                int phase;

                for (phase = 0; phase < info->phases[page];
                     phase++) {
                    if (!(info->pfunc[phase] & attrs->func))
                        continue;
                    ret = pmbus_add_sensor_attrs_one(client,
                        data, info, name, index, page,
                        phase, attrs, paged);
                    if (ret)
                        return ret;
                    index++;
                }
            }
        }
        attrs++;
    }
    return 0;
}

static const struct pmbus_limit_attr vin_limit_attrs[] = {
    {
        .reg = PMBUS_VIN_UV_WARN_LIMIT,
        .attr = "min",
        .alarm = "min_alarm",
        .sbit = PB_VOLTAGE_UV_WARNING,
    }, {
        .reg = PMBUS_VIN_UV_FAULT_LIMIT,
        .attr = "lcrit",
        .alarm = "lcrit_alarm",
        .sbit = PB_VOLTAGE_UV_FAULT,
    }, {
        .reg = PMBUS_VIN_OV_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_VOLTAGE_OV_WARNING,
    }, {
        .reg = PMBUS_VIN_OV_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_VOLTAGE_OV_FAULT,
    }, {
        .reg = PMBUS_VIRT_READ_VIN_AVG,
        .update = true,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_VIN_MIN,
        .update = true,
        .attr = "lowest",
    }, {
        .reg = PMBUS_VIRT_READ_VIN_MAX,
        .update = true,
        .attr = "highest",
    }, {
        .reg = PMBUS_VIRT_RESET_VIN_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_VIN_MIN,
        .attr = "rated_min",
    }, {
        .reg = PMBUS_MFR_VIN_MAX,
        .attr = "rated_max",
    },
};

static const struct pmbus_limit_attr vmon_limit_attrs[] = {
    {
        .reg = PMBUS_VIRT_VMON_UV_WARN_LIMIT,
        .attr = "min",
        .alarm = "min_alarm",
        .sbit = PB_VOLTAGE_UV_WARNING,
    }, {
        .reg = PMBUS_VIRT_VMON_UV_FAULT_LIMIT,
        .attr = "lcrit",
        .alarm = "lcrit_alarm",
        .sbit = PB_VOLTAGE_UV_FAULT,
    }, {
        .reg = PMBUS_VIRT_VMON_OV_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_VOLTAGE_OV_WARNING,
    }, {
        .reg = PMBUS_VIRT_VMON_OV_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_VOLTAGE_OV_FAULT,
    }
};

static const struct pmbus_limit_attr vout_limit_attrs[] = {
    {
        .reg = PMBUS_VOUT_UV_WARN_LIMIT,
        .attr = "min",
        .alarm = "min_alarm",
        .sbit = PB_VOLTAGE_UV_WARNING,
    }, {
        .reg = PMBUS_VOUT_UV_FAULT_LIMIT,
        .attr = "lcrit",
        .alarm = "lcrit_alarm",
        .sbit = PB_VOLTAGE_UV_FAULT,
    }, {
        .reg = PMBUS_VOUT_OV_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_VOLTAGE_OV_WARNING,
    }, {
        .reg = PMBUS_VOUT_OV_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_VOLTAGE_OV_FAULT,
    }, {
        .reg = PMBUS_VIRT_READ_VOUT_AVG,
        .update = true,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_VOUT_MIN,
        .update = true,
        .attr = "lowest",
    }, {
        .reg = PMBUS_VIRT_READ_VOUT_MAX,
        .update = true,
        .attr = "highest",
    }, {
        .reg = PMBUS_VIRT_RESET_VOUT_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_VOUT_MIN,
        .attr = "rated_min",
    }, {
        .reg = PMBUS_MFR_VOUT_MAX,
        .attr = "rated_max",
    },
};

static const struct pmbus_sensor_attr voltage_attributes[] = {
    {
        .reg = PMBUS_READ_VIN,
        .class = PSC_VOLTAGE_IN,
        .label = "vin",
        .func = PMBUS_HAVE_VIN,
        .sfunc = PMBUS_HAVE_STATUS_INPUT,
        .sreg = PMBUS_STATUS_INPUT,
        .gbit = PB_STATUS_VIN_UV,
        .limit = vin_limit_attrs,
        .nlimit = ARRAY_SIZE(vin_limit_attrs),
    }, {
        .reg = PMBUS_VIRT_READ_VMON,
        .class = PSC_VOLTAGE_IN,
        .label = "vmon",
        .func = PMBUS_HAVE_VMON,
        .sfunc = PMBUS_HAVE_STATUS_VMON,
        .sreg = PMBUS_VIRT_STATUS_VMON,
        .limit = vmon_limit_attrs,
        .nlimit = ARRAY_SIZE(vmon_limit_attrs),
    }, {
        .reg = PMBUS_READ_VCAP,
        .class = PSC_VOLTAGE_IN,
        .label = "vcap",
        .func = PMBUS_HAVE_VCAP,
    }, {
        .reg = PMBUS_READ_VOUT,
        .class = PSC_VOLTAGE_OUT,
        .label = "vout",
        .paged = true,
        .func = PMBUS_HAVE_VOUT,
        .sfunc = PMBUS_HAVE_STATUS_VOUT,
        .sreg = PMBUS_STATUS_VOUT,
        .gbit = PB_STATUS_VOUT_OV,
        .limit = vout_limit_attrs,
        .nlimit = ARRAY_SIZE(vout_limit_attrs),
    }
};

/* Current attributes */

static const struct pmbus_limit_attr iin_limit_attrs[] = {
    {
        .reg = PMBUS_IIN_OC_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_IIN_OC_WARNING,
    }, {
        .reg = PMBUS_IIN_OC_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_IIN_OC_FAULT,
    }, {
        .reg = PMBUS_VIRT_READ_IIN_AVG,
        .update = true,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_IIN_MIN,
        .update = true,
        .attr = "lowest",
    }, {
        .reg = PMBUS_VIRT_READ_IIN_MAX,
        .update = true,
        .attr = "highest",
    }, {
        .reg = PMBUS_VIRT_RESET_IIN_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_IIN_MAX,
        .attr = "rated_max",
    },
};

static const struct pmbus_limit_attr iout_limit_attrs[] = {
    {
        .reg = PMBUS_IOUT_OC_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_IOUT_OC_WARNING,
    }, {
        .reg = PMBUS_IOUT_UC_FAULT_LIMIT,
        .attr = "lcrit",
        .alarm = "lcrit_alarm",
        .sbit = PB_IOUT_UC_FAULT,
    }, {
        .reg = PMBUS_IOUT_OC_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_IOUT_OC_FAULT,
    }, {
        .reg = PMBUS_VIRT_READ_IOUT_AVG,
        .update = true,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_IOUT_MIN,
        .update = true,
        .attr = "lowest",
    }, {
        .reg = PMBUS_VIRT_READ_IOUT_MAX,
        .update = true,
        .attr = "highest",
    }, {
        .reg = PMBUS_VIRT_RESET_IOUT_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_IOUT_MAX,
        .attr = "rated_max",
    },
};

static const struct pmbus_sensor_attr current_attributes[] = {
    {
        .reg = PMBUS_READ_IIN,
        .class = PSC_CURRENT_IN,
        .label = "iin",
        .func = PMBUS_HAVE_IIN,
        .sfunc = PMBUS_HAVE_STATUS_INPUT,
        .sreg = PMBUS_STATUS_INPUT,
        .gbit = PB_STATUS_INPUT,
        .limit = iin_limit_attrs,
        .nlimit = ARRAY_SIZE(iin_limit_attrs),
    }, {
        .reg = PMBUS_READ_IOUT,
        .class = PSC_CURRENT_OUT,
        .label = "iout",
        .paged = true,
        .func = PMBUS_HAVE_IOUT,
        .sfunc = PMBUS_HAVE_STATUS_IOUT,
        .sreg = PMBUS_STATUS_IOUT,
        .gbit = PB_STATUS_IOUT_OC,
        .limit = iout_limit_attrs,
        .nlimit = ARRAY_SIZE(iout_limit_attrs),
    }
};

/* Power attributes */

static const struct pmbus_limit_attr pin_limit_attrs[] = {
    {
        .reg = PMBUS_PIN_OP_WARN_LIMIT,
        .attr = "max",
        .alarm = "alarm",
        .sbit = PB_PIN_OP_WARNING,
    }, {
        .reg = PMBUS_VIRT_READ_PIN_AVG,
        .update = true,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_PIN_MIN,
        .update = true,
        .attr = "input_lowest",
    }, {
        .reg = PMBUS_VIRT_READ_PIN_MAX,
        .update = true,
        .attr = "input_highest",
    }, {
        .reg = PMBUS_VIRT_RESET_PIN_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_PIN_MAX,
        .attr = "rated_max",
    },
};

static const struct pmbus_limit_attr pout_limit_attrs[] = {
    {
        .reg = PMBUS_POUT_MAX,
        .attr = "cap",
        .alarm = "cap_alarm",
        .sbit = PB_POWER_LIMITING,
    }, {
        .reg = PMBUS_POUT_OP_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_POUT_OP_WARNING,
    }, {
        .reg = PMBUS_POUT_OP_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_POUT_OP_FAULT,
    }, {
        .reg = PMBUS_VIRT_READ_POUT_AVG,
        .update = true,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_POUT_MIN,
        .update = true,
        .attr = "input_lowest",
    }, {
        .reg = PMBUS_VIRT_READ_POUT_MAX,
        .update = true,
        .attr = "input_highest",
    }, {
        .reg = PMBUS_VIRT_RESET_POUT_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_POUT_MAX,
        .attr = "rated_max",
    },
};

static const struct pmbus_sensor_attr power_attributes[] = {
    {
        .reg = PMBUS_READ_PIN,
        .class = PSC_POWER,
        .label = "pin",
        .func = PMBUS_HAVE_PIN,
        .sfunc = PMBUS_HAVE_STATUS_INPUT,
        .sreg = PMBUS_STATUS_INPUT,
        .gbit = PB_STATUS_INPUT,
        .limit = pin_limit_attrs,
        .nlimit = ARRAY_SIZE(pin_limit_attrs),
    }, {
        .reg = PMBUS_READ_POUT,
        .class = PSC_POWER,
        .label = "pout",
        .paged = true,
        .func = PMBUS_HAVE_POUT,
        .sfunc = PMBUS_HAVE_STATUS_IOUT,
        .sreg = PMBUS_STATUS_IOUT,
        .limit = pout_limit_attrs,
        .nlimit = ARRAY_SIZE(pout_limit_attrs),
    }
};

/* Temperature atributes */

static const struct pmbus_limit_attr temp_limit_attrs[] = {
    {
        .reg = PMBUS_UT_WARN_LIMIT,
        .low = true,
        .attr = "min",
        .alarm = "min_alarm",
        .sbit = PB_TEMP_UT_WARNING,
    }, {
        .reg = PMBUS_UT_FAULT_LIMIT,
        .low = true,
        .attr = "lcrit",
        .alarm = "lcrit_alarm",
        .sbit = PB_TEMP_UT_FAULT,
    }, {
        .reg = PMBUS_OT_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_TEMP_OT_WARNING,
    }, {
        .reg = PMBUS_OT_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_TEMP_OT_FAULT,
    }, {
        .reg = PMBUS_VIRT_READ_TEMP_MIN,
        .attr = "lowest",
    }, {
        .reg = PMBUS_VIRT_READ_TEMP_AVG,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_TEMP_MAX,
        .attr = "highest",
    }, {
        .reg = PMBUS_VIRT_RESET_TEMP_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_MAX_TEMP_1,
        .attr = "rated_max",
    },
};

static const struct pmbus_limit_attr temp_limit_attrs2[] = {
    {
        .reg = PMBUS_UT_WARN_LIMIT,
        .low = true,
        .attr = "min",
        .alarm = "min_alarm",
        .sbit = PB_TEMP_UT_WARNING,
    }, {
        .reg = PMBUS_UT_FAULT_LIMIT,
        .low = true,
        .attr = "lcrit",
        .alarm = "lcrit_alarm",
        .sbit = PB_TEMP_UT_FAULT,
    }, {
        .reg = PMBUS_OT_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_TEMP_OT_WARNING,
    }, {
        .reg = PMBUS_OT_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_TEMP_OT_FAULT,
    }, {
        .reg = PMBUS_VIRT_READ_TEMP2_MIN,
        .attr = "lowest",
    }, {
        .reg = PMBUS_VIRT_READ_TEMP2_AVG,
        .attr = "average",
    }, {
        .reg = PMBUS_VIRT_READ_TEMP2_MAX,
        .attr = "highest",
    }, {
        .reg = PMBUS_VIRT_RESET_TEMP2_HISTORY,
        .attr = "reset_history",
    }, {
        .reg = PMBUS_MFR_MAX_TEMP_2,
        .attr = "rated_max",
    },
};

static const struct pmbus_limit_attr temp_limit_attrs3[] = {
    {
        .reg = PMBUS_UT_WARN_LIMIT,
        .low = true,
        .attr = "min",
        .alarm = "min_alarm",
        .sbit = PB_TEMP_UT_WARNING,
    }, {
        .reg = PMBUS_UT_FAULT_LIMIT,
        .low = true,
        .attr = "lcrit",
        .alarm = "lcrit_alarm",
        .sbit = PB_TEMP_UT_FAULT,
    }, {
        .reg = PMBUS_OT_WARN_LIMIT,
        .attr = "max",
        .alarm = "max_alarm",
        .sbit = PB_TEMP_OT_WARNING,
    }, {
        .reg = PMBUS_OT_FAULT_LIMIT,
        .attr = "crit",
        .alarm = "crit_alarm",
        .sbit = PB_TEMP_OT_FAULT,
    }, {
        .reg = PMBUS_MFR_MAX_TEMP_3,
        .attr = "rated_max",
    },
};

static const struct pmbus_sensor_attr temp_attributes[] = {
    {
        .reg = PMBUS_READ_TEMPERATURE_1,
        .class = PSC_TEMPERATURE,
        .paged = true,
        .update = true,
        .compare = true,
        .func = PMBUS_HAVE_TEMP,
        .sfunc = PMBUS_HAVE_STATUS_TEMP,
        .sreg = PMBUS_STATUS_TEMPERATURE,
        .gbit = PB_STATUS_TEMPERATURE,
        .limit = temp_limit_attrs,
        .nlimit = ARRAY_SIZE(temp_limit_attrs),
    }, {
        .reg = PMBUS_READ_TEMPERATURE_2,
        .class = PSC_TEMPERATURE,
        .paged = true,
        .update = true,
        .compare = true,
        .func = PMBUS_HAVE_TEMP2,
        .sfunc = PMBUS_HAVE_STATUS_TEMP,
        .sreg = PMBUS_STATUS_TEMPERATURE,
        .gbit = PB_STATUS_TEMPERATURE,
        .limit = temp_limit_attrs2,
        .nlimit = ARRAY_SIZE(temp_limit_attrs2),
    }, {
        .reg = PMBUS_READ_TEMPERATURE_3,
        .class = PSC_TEMPERATURE,
        .paged = true,
        .update = true,
        .compare = true,
        .func = PMBUS_HAVE_TEMP3,
        .sfunc = PMBUS_HAVE_STATUS_TEMP,
        .sreg = PMBUS_STATUS_TEMPERATURE,
        .gbit = PB_STATUS_TEMPERATURE,
        .limit = temp_limit_attrs3,
        .nlimit = ARRAY_SIZE(temp_limit_attrs3),
    }
};

static const int pmbus_fan_registers[] = {
    PMBUS_READ_FAN_SPEED_1,
    PMBUS_READ_FAN_SPEED_2,
    PMBUS_READ_FAN_SPEED_3,
    PMBUS_READ_FAN_SPEED_4
};

static const int pmbus_fan_status_registers[] = {
    PMBUS_STATUS_FAN_12,
    PMBUS_STATUS_FAN_12,
    PMBUS_STATUS_FAN_34,
    PMBUS_STATUS_FAN_34
};

static const u32 pmbus_fan_flags[] = {
    PMBUS_HAVE_FAN12,
    PMBUS_HAVE_FAN12,
    PMBUS_HAVE_FAN34,
    PMBUS_HAVE_FAN34
};

static const u32 pmbus_fan_status_flags[] = {
    PMBUS_HAVE_STATUS_FAN12,
    PMBUS_HAVE_STATUS_FAN12,
    PMBUS_HAVE_STATUS_FAN34,
    PMBUS_HAVE_STATUS_FAN34
};

/* Fans */

/* Precondition: FAN_CONFIG_x_y and FAN_COMMAND_x must exist for the fan ID */
static int pmbus_add_fan_ctrl(struct i2c_client *client,
        struct pmbus_data *data, int index, int page, int id,
        u8 config)
{
    struct pmbus_sensor *sensor;

    sensor = pmbus_add_sensor(data, "fan", "target", index, page,
                  0xff, PMBUS_VIRT_FAN_TARGET_1 + id, PSC_FAN,
                  false, false, true);

    if (!sensor)
        return -ENOMEM;

    if (!((data->info->func[page] & PMBUS_HAVE_PWM12) ||
            (data->info->func[page] & PMBUS_HAVE_PWM34)))
        return 0;

    sensor = pmbus_add_sensor(data, "pwm", NULL, index, page,
                  0xff, PMBUS_VIRT_PWM_1 + id, PSC_PWM,
                  false, false, true);

    if (!sensor)
        return -ENOMEM;

    sensor = pmbus_add_sensor(data, "pwm", "enable", index, page,
                  0xff, PMBUS_VIRT_PWM_ENABLE_1 + id, PSC_PWM,
                  true, false, false);

    if (!sensor)
        return -ENOMEM;

    return 0;
}

static int pmbus_add_fan_attributes(struct i2c_client *client,
                    struct pmbus_data *data)
{
    const struct pmbus_driver_info *info = data->info;
    int index = 1;
    int page;
    int ret;

    for (page = 0; page < info->pages; page++) {
        int f;

        for (f = 0; f < ARRAY_SIZE(pmbus_fan_registers); f++) {
            int regval;

            if (!(info->func[page] & pmbus_fan_flags[f]))
                break;

            if (!wb_pmbus_check_word_register(client, page,
                               pmbus_fan_registers[f]))
                break;

            /*
             * Skip fan if not installed.
             * Each fan configuration register covers multiple fans,
             * so we have to do some magic.
             */
            regval = _pmbus_read_byte_data(client, page,
                pmbus_fan_config_registers[f]);
            if (regval < 0 ||
                (!(regval & (PB_FAN_1_INSTALLED >> ((f & 1) * 4)))))
                continue;

            if (pmbus_add_sensor(data, "fan", "input", index,
                         page, 0xff, pmbus_fan_registers[f],
                         PSC_FAN, true, true, true) == NULL)
                return -ENOMEM;

            /* Fan control */
            if (wb_pmbus_check_word_register(client, page,
                    pmbus_fan_command_registers[f])) {
                ret = pmbus_add_fan_ctrl(client, data, index,
                             page, f, regval);
                if (ret < 0)
                    return ret;
            }

            /*
             * Each fan status register covers multiple fans,
             * so we have to do some magic.
             */
            if ((info->func[page] & pmbus_fan_status_flags[f]) &&
                wb_pmbus_check_byte_register(client,
                    page, pmbus_fan_status_registers[f])) {
                int reg;

                if (f > 1)    /* fan 3, 4 */
                    reg = PMBUS_STATUS_FAN_34;
                else
                    reg = PMBUS_STATUS_FAN_12;
                ret = pmbus_add_boolean(data, "fan",
                    "alarm", index, NULL, NULL, page, reg,
                    PB_FAN_FAN1_WARNING >> (f & 1));
                if (ret)
                    return ret;
                ret = pmbus_add_boolean(data, "fan",
                    "fault", index, NULL, NULL, page, reg,
                    PB_FAN_FAN1_FAULT >> (f & 1));
                if (ret)
                    return ret;
            }
            index++;
        }
    }
    return 0;
}

struct pmbus_samples_attr {
    int reg;
    char *name;
};

struct pmbus_samples_reg {
    int page;
    struct pmbus_samples_attr *attr;
    struct device_attribute dev_attr;
};

static struct pmbus_samples_attr pmbus_samples_registers[] = {
    {
        .reg = PMBUS_VIRT_SAMPLES,
        .name = "samples",
    }, {
        .reg = PMBUS_VIRT_IN_SAMPLES,
        .name = "in_samples",
    }, {
        .reg = PMBUS_VIRT_CURR_SAMPLES,
        .name = "curr_samples",
    }, {
        .reg = PMBUS_VIRT_POWER_SAMPLES,
        .name = "power_samples",
    }, {
        .reg = PMBUS_VIRT_TEMP_SAMPLES,
        .name = "temp_samples",
    }
};

#define to_samples_reg(x) container_of(x, struct pmbus_samples_reg, dev_attr)

static ssize_t pmbus_show_samples(struct device *dev,
                  struct device_attribute *devattr, char *buf)
{
    int val;
    struct i2c_client *client = to_i2c_client(dev->parent);
    struct pmbus_samples_reg *reg = to_samples_reg(devattr);
    struct pmbus_data *data = i2c_get_clientdata(client);

    mutex_lock(&data->update_lock);
    val = _pmbus_read_word_data(client, reg->page, 0xff, reg->attr->reg);
    mutex_unlock(&data->update_lock);
    if (val < 0)
        return val;

    return snprintf(buf, PAGE_SIZE, "%d\n", val);
}

static ssize_t pmbus_set_samples(struct device *dev,
                 struct device_attribute *devattr,
                 const char *buf, size_t count)
{
    int ret;
    long val;
    struct i2c_client *client = to_i2c_client(dev->parent);
    struct pmbus_samples_reg *reg = to_samples_reg(devattr);
    struct pmbus_data *data = i2c_get_clientdata(client);

    if (kstrtol(buf, 0, &val) < 0)
        return -EINVAL;

    mutex_lock(&data->update_lock);
    ret = _pmbus_write_word_data(client, reg->page, reg->attr->reg, val);
    mutex_unlock(&data->update_lock);

    return ret ? : count;
}

static int pmbus_add_samples_attr(struct pmbus_data *data, int page,
                  struct pmbus_samples_attr *attr)
{
    struct pmbus_samples_reg *reg;

    reg = devm_kzalloc(data->dev, sizeof(*reg), GFP_KERNEL);
    if (!reg)
        return -ENOMEM;

    reg->attr = attr;
    reg->page = page;

    pmbus_dev_attr_init(&reg->dev_attr, attr->name, 0644,
                pmbus_show_samples, pmbus_set_samples);

    return pmbus_add_attribute(data, &reg->dev_attr.attr);
}

static int pmbus_add_samples_attributes(struct i2c_client *client,
                    struct pmbus_data *data)
{
    const struct pmbus_driver_info *info = data->info;
    int s;

    if (!(info->func[0] & PMBUS_HAVE_SAMPLES))
        return 0;

    for (s = 0; s < ARRAY_SIZE(pmbus_samples_registers); s++) {
        struct pmbus_samples_attr *attr;
        int ret;

        attr = &pmbus_samples_registers[s];
        if (!wb_pmbus_check_word_register(client, 0, attr->reg))
            continue;

        ret = pmbus_add_samples_attr(data, 0, attr);
        if (ret)
            return ret;
    }

    return 0;
}

static int pmbus_find_attributes(struct i2c_client *client,
                 struct pmbus_data *data)
{
    int ret;

    /* Voltage sensors */
    ret = pmbus_add_sensor_attrs(client, data, "in", voltage_attributes,
                     ARRAY_SIZE(voltage_attributes));
    if (ret)
        return ret;

    /* Current sensors */
    ret = pmbus_add_sensor_attrs(client, data, "curr", current_attributes,
                     ARRAY_SIZE(current_attributes));
    if (ret)
        return ret;

    /* Power sensors */
    ret = pmbus_add_sensor_attrs(client, data, "power", power_attributes,
                     ARRAY_SIZE(power_attributes));
    if (ret)
        return ret;

    /* Temperature sensors */
    ret = pmbus_add_sensor_attrs(client, data, "temp", temp_attributes,
                     ARRAY_SIZE(temp_attributes));
    if (ret)
        return ret;

    /* Fans */
    ret = pmbus_add_fan_attributes(client, data);
    if (ret)
        return ret;

    ret = pmbus_add_samples_attributes(client, data);
    return ret;
}

/*
 * Identify chip parameters.
 * This function is called for all chips.
 */
static int pmbus_identify_common(struct i2c_client *client,
                 struct pmbus_data *data, int page)
{
    int vout_mode = -1;

    if (wb_pmbus_check_byte_register(client, page, PMBUS_VOUT_MODE))
        vout_mode = _pmbus_read_byte_data(client, page,
                          PMBUS_VOUT_MODE);
    if (vout_mode >= 0 && vout_mode != 0xff) {
        /*
         * Not all chips support the VOUT_MODE command,
         * so a failure to read it is not an error.
         */
        switch (vout_mode >> 5) {
        case 0:    /* linear mode      */
            if (data->info->format[PSC_VOLTAGE_OUT] != linear)
                return -ENODEV;

            data->exponent[page] = ((s8)(vout_mode << 3)) >> 3;
            break;
        case 1: /* VID mode         */
            if (data->info->format[PSC_VOLTAGE_OUT] != vid)
                return -ENODEV;
            break;
        case 2:    /* direct mode      */
            if (data->info->format[PSC_VOLTAGE_OUT] != direct)
                return -ENODEV;
            break;
        default:
            return -ENODEV;
        }
    }

    pmbus_clear_fault_page(client, page);
    return 0;
}

static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data,
                 struct pmbus_driver_info *info)
{
    struct device *dev = &client->dev;
    int page, ret, i;

    /*
     * Some PMBus chips don't support PMBUS_STATUS_WORD, so try
     * to use PMBUS_STATUS_BYTE instead if that is the case.
     * Bail out if both registers are not supported.
     */
    for(i = 0; i < PMBUS_RETRY_TIME; i++) {
        data->read_status = pmbus_read_status_word;
        ret = i2c_smbus_read_word_data(client, PMBUS_STATUS_WORD);
        if (ret < 0 || ret == 0xffff) {
            data->read_status = pmbus_read_status_byte;
            ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE);
            if (ret < 0 || ret == 0xff) {
                usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
                continue;
            }
        } else {
            data->has_status_word = true;
        }
        break;
    }

    if(i == PMBUS_RETRY_TIME) {
        dev_err(dev, "PMBus status register not found\n");
        return -ENODEV;
    }

    /* Enable PEC if the controller supports it */
    for(i = 0; i < PMBUS_RETRY_TIME; i++) {
        ret = i2c_smbus_read_byte_data(client, PMBUS_CAPABILITY);
        if (ret >= 0) {
            break;
        }
        usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
    }

    if (ret >= 0 && (ret & PB_CAPABILITY_ERROR_CHECK))
        client->flags |= I2C_CLIENT_PEC;

    /*
     * Check if the chip is write protected. If it is, we can not clear
     * faults, and we should not try it. Also, in that case, writes into
     * limit registers need to be disabled.
     */
    for(i = 0; i < PMBUS_RETRY_TIME; i++) {
        ret = i2c_smbus_read_byte_data(client, PMBUS_WRITE_PROTECT);
        if (ret >= 0) {
            break;
        }
        usleep_range(PMBUS_RETRY_SLEEP_TIME, PMBUS_RETRY_SLEEP_TIME + 1);
    }

    if (ret > 0 && (ret & PB_WP_ANY))
        data->flags |= PMBUS_WRITE_PROTECTED | PMBUS_SKIP_STATUS_CHECK;

    if (data->info->pages)
        wb_pmbus_clear_faults(client);
    else
        pmbus_clear_fault_page(client, -1);

    if (info->identify) {
        ret = (*info->identify)(client, info);
        if (ret < 0) {
            dev_err(dev, "Chip identification failed\n");
            return ret;
        }
    }

    if (info->pages <= 0 || info->pages > PMBUS_PAGES) {
        dev_err(dev, "Bad number of PMBus pages: %d\n", info->pages);
        return -ENODEV;
    }

    for (page = 0; page < info->pages; page++) {
        ret = pmbus_identify_common(client, data, page);
        if (ret < 0) {
            dev_err(dev, "Failed to identify chip capabilities\n");
            return ret;
        }
    }
    return 0;
}

#if IS_ENABLED(CONFIG_REGULATOR)
static int pmbus_regulator_is_enabled(struct regulator_dev *rdev)
{
    struct device *dev = rdev_get_dev(rdev);
    struct i2c_client *client = to_i2c_client(dev->parent);
    u8 page = rdev_get_id(rdev);
    int ret;

    ret = wb_pmbus_read_byte_data(client, page, PMBUS_OPERATION);
    if (ret < 0)
        return ret;

    return !!(ret & PB_OPERATION_CONTROL_ON);
}

static int _pmbus_regulator_on_off(struct regulator_dev *rdev, bool enable)
{
    struct device *dev = rdev_get_dev(rdev);
    struct i2c_client *client = to_i2c_client(dev->parent);
    u8 page = rdev_get_id(rdev);

    return wb_pmbus_update_byte_data(client, page, PMBUS_OPERATION,
                      PB_OPERATION_CONTROL_ON,
                      enable ? PB_OPERATION_CONTROL_ON : 0);
}

static int pmbus_regulator_enable(struct regulator_dev *rdev)
{
    return _pmbus_regulator_on_off(rdev, 1);
}

static int pmbus_regulator_disable(struct regulator_dev *rdev)
{
    return _pmbus_regulator_on_off(rdev, 0);
}

const struct regulator_ops wb_pmbus_regulator_ops = {
    .enable = pmbus_regulator_enable,
    .disable = pmbus_regulator_disable,
    .is_enabled = pmbus_regulator_is_enabled,
};
EXPORT_SYMBOL_GPL(wb_pmbus_regulator_ops);

static int pmbus_regulator_register(struct pmbus_data *data)
{
    struct device *dev = data->dev;
    const struct pmbus_driver_info *info = data->info;
    const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
    struct regulator_dev *rdev;
    int i;

    for (i = 0; i < info->num_regulators; i++) {
        struct regulator_config config = { };

        config.dev = dev;
        config.driver_data = data;

        if (pdata && pdata->reg_init_data)
            config.init_data = &pdata->reg_init_data[i];

        rdev = devm_regulator_register(dev, &info->reg_desc[i],
                           &config);
        if (IS_ERR(rdev)) {
            dev_err(dev, "Failed to register %s regulator\n",
                info->reg_desc[i].name);
            return PTR_ERR(rdev);
        }
    }

    return 0;
}
#else
static int pmbus_regulator_register(struct pmbus_data *data)
{
    return 0;
}
#endif

static struct dentry *pmbus_debugfs_dir;    /* pmbus debugfs directory */

#if IS_ENABLED(CONFIG_DEBUG_FS)
static int pmbus_debugfs_get(void *data, u64 *val)
{
    int rc;
    struct pmbus_debugfs_entry *entry = data;

    rc = _pmbus_read_byte_data(entry->client, entry->page, entry->reg);
    if (rc < 0)
        return rc;

    *val = rc;

    return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops, pmbus_debugfs_get, NULL,
             "0x%02llx\n");

static int pmbus_debugfs_get_status(void *data, u64 *val)
{
    int rc;
    struct pmbus_debugfs_entry *entry = data;
    struct pmbus_data *pdata = i2c_get_clientdata(entry->client);

    rc = pdata->read_status(entry->client, entry->page);
    if (rc < 0)
        return rc;

    *val = rc;

    return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops_status, pmbus_debugfs_get_status,
             NULL, "0x%04llx\n");

static int pmbus_debugfs_get_pec(void *data, u64 *val)
{
    struct i2c_client *client = data;

    *val = !!(client->flags & I2C_CLIENT_PEC);

    return 0;
}

static int pmbus_debugfs_set_pec(void *data, u64 val)
{
    int rc;
    struct i2c_client *client = data;

    if (!val) {
        client->flags &= ~I2C_CLIENT_PEC;
        return 0;
    }

    if (val != 1)
        return -EINVAL;

    rc = i2c_smbus_read_byte_data(client, PMBUS_CAPABILITY);
    if (rc < 0)
        return rc;

    if (!(rc & PB_CAPABILITY_ERROR_CHECK))
        return -EOPNOTSUPP;

    client->flags |= I2C_CLIENT_PEC;

    return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops_pec, pmbus_debugfs_get_pec,
             pmbus_debugfs_set_pec, "%llu\n");

static int pmbus_init_debugfs(struct i2c_client *client,
                  struct pmbus_data *data)
{
    int i, idx = 0;
    char name[PMBUS_NAME_SIZE];
    struct pmbus_debugfs_entry *entries;

    if (!pmbus_debugfs_dir)
        return -ENODEV;

    /*
     * Create the debugfs directory for this device. Use the hwmon device
     * name to avoid conflicts (hwmon numbers are globally unique).
     */
    data->debugfs = debugfs_create_dir(dev_name(data->hwmon_dev),
                       pmbus_debugfs_dir);
    if (IS_ERR_OR_NULL(data->debugfs)) {
        data->debugfs = NULL;
        return -ENODEV;
    }

    /* Allocate the max possible entries we need. */
    entries = devm_kcalloc(data->dev,
                   data->info->pages * 10, sizeof(*entries),
                   GFP_KERNEL);
    if (!entries)
        return -ENOMEM;

    debugfs_create_file("pec", 0664, data->debugfs, client,
                &pmbus_debugfs_ops_pec);

    for (i = 0; i < data->info->pages; ++i) {
        /* Check accessibility of status register if it's not page 0 */
        if (!i || pmbus_check_status_register(client, i)) {
            /* No need to set reg as we have special read op. */
            entries[idx].client = client;
            entries[idx].page = i;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops_status);
        }

        if (data->info->func[i] & PMBUS_HAVE_STATUS_VOUT) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_VOUT;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_vout", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (data->info->func[i] & PMBUS_HAVE_STATUS_IOUT) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_IOUT;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_iout", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (data->info->func[i] & PMBUS_HAVE_STATUS_INPUT) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_INPUT;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_input", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (data->info->func[i] & PMBUS_HAVE_STATUS_TEMP) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_TEMPERATURE;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_temp", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (wb_pmbus_check_byte_register(client, i, PMBUS_STATUS_CML)) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_CML;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_cml", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (wb_pmbus_check_byte_register(client, i, PMBUS_STATUS_OTHER)) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_OTHER;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_other", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (wb_pmbus_check_byte_register(client, i,
                          PMBUS_STATUS_MFR_SPECIFIC)) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_MFR_SPECIFIC;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_mfr", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (data->info->func[i] & PMBUS_HAVE_STATUS_FAN12) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_FAN_12;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_fan12", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }

        if (data->info->func[i] & PMBUS_HAVE_STATUS_FAN34) {
            entries[idx].client = client;
            entries[idx].page = i;
            entries[idx].reg = PMBUS_STATUS_FAN_34;
            scnprintf(name, PMBUS_NAME_SIZE, "status%d_fan34", i);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[idx++],
                        &pmbus_debugfs_ops);
        }
    }

    return 0;
}
#else
static int pmbus_init_debugfs(struct i2c_client *client,
                  struct pmbus_data *data)
{
    return 0;
}
#endif    /* IS_ENABLED(CONFIG_DEBUG_FS) */

int wb_pmbus_do_probe(struct i2c_client *client, struct pmbus_driver_info *info)
{
    struct device *dev = &client->dev;
    const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
    struct pmbus_data *data;
    size_t groups_num = 0;
    int ret;

    if (!info)
        return -ENODEV;

    if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE
                     | I2C_FUNC_SMBUS_BYTE_DATA
                     | I2C_FUNC_SMBUS_WORD_DATA))
        return -ENODEV;

    data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
    if (!data)
        return -ENOMEM;

    if (info->groups)
        while (info->groups[groups_num])
            groups_num++;

    data->groups = devm_kcalloc(dev, groups_num + 2, sizeof(void *),
                    GFP_KERNEL);
    if (!data->groups)
        return -ENOMEM;

    i2c_set_clientdata(client, data);
    mutex_init(&data->update_lock);
    data->dev = dev;

    if (pdata)
        data->flags = pdata->flags;
    data->info = info;
    data->currpage = -1;
    data->currphase = -1;

    ret = pmbus_init_common(client, data, info);
    if (ret < 0)
        return ret;

    ret = pmbus_find_attributes(client, data);
    if (ret)
        return ret;

    /*
     * If there are no attributes, something is wrong.
     * Bail out instead of trying to register nothing.
     */
    if (!data->num_attributes) {
        dev_err(dev, "No attributes found\n");
        return -ENODEV;
    }

    data->groups[0] = &data->group;
    memcpy(data->groups + 1, info->groups, sizeof(void *) * groups_num);
    data->hwmon_dev = devm_hwmon_device_register_with_groups(dev,
                    client->name, data, data->groups);
    if (IS_ERR(data->hwmon_dev)) {
        dev_err(dev, "Failed to register hwmon device\n");
        return PTR_ERR(data->hwmon_dev);
    }

    ret = pmbus_regulator_register(data);
    if (ret)
        return ret;

    ret = pmbus_init_debugfs(client, data);
    if (ret)
        dev_warn(dev, "Failed to register debugfs\n");

    return 0;
}
EXPORT_SYMBOL_GPL(wb_pmbus_do_probe);

int wb_pmbus_do_remove(struct i2c_client *client)
{
    struct pmbus_data *data = i2c_get_clientdata(client);

    debugfs_remove_recursive(data->debugfs);

    return 0;
}
EXPORT_SYMBOL_GPL(wb_pmbus_do_remove);

struct dentry *wb_pmbus_get_debugfs_dir(struct i2c_client *client)
{
    struct pmbus_data *data = i2c_get_clientdata(client);

    return data->debugfs;
}
EXPORT_SYMBOL_GPL(wb_pmbus_get_debugfs_dir);

static int __init pmbus_core_init(void)
{
    pmbus_debugfs_dir = debugfs_create_dir("pmbus", NULL);
    if (IS_ERR(pmbus_debugfs_dir))
        pmbus_debugfs_dir = NULL;

    return 0;
}

static void __exit pmbus_core_exit(void)
{
    debugfs_remove_recursive(pmbus_debugfs_dir);
}

module_init(pmbus_core_init);
module_exit(pmbus_core_exit);

MODULE_AUTHOR("support");
MODULE_DESCRIPTION("PMBus core driver");
MODULE_LICENSE("GPL");
